need help im a bit confused

[stiofanpadraigcrafts]

Hi guys, i just started to make my first kitless pen, i made the section ( on my second attempt after a mistake ) and all looks good. So i drilled the body on the lathe then proceeded to thread it using the matching Tap 10 x 0.75 tap and die. the problem i have is that the section seems to small for the body. it just bounces about inside. I'm using a split die so maybe i made a mistake there, i dont know. Could i have overtightened the die? or have i done something else that you can think of? any help at ll would b appreciated thanks guys

 

[Penpal]

Measurements, pictures help.

Peter.

 

[stiofanpadraigcrafts]

Sorry Peter, never even thought. The body is 9.25 so it is ok but the section measures 9.1 so im thinking i overtightened the die

 

[Buckeye]

On the die holder there should be 3 grub screws if you position the die so that the split lines up with the middle grub screw and tighten it gently so as not to force to open, but to allow the grub screw to sit in the split when you tighten the other two gently to hold the die in place you shouldn't be able to close the die up. Try that on a scrap piece and check to see if you have a better fit, if it is still rattling inside then open the outer two screws and tighten the middle one a bit more to open up the die a little, just keep doing that until you find the right setting.

Peter

 

[stiofanpadraigcrafts]

Thanks for the advice thats great

 

[Phil Dart]

Stephen, it's unlikely to be down to the die to be honest. If you think it through, the crest of the male thread is what is left behind by the negative space of the die's major diameter, which is not is not a cutting surface. The trough of the male thread is what is cut by the die. The only way you can over egg the cake throgh over tightening a split die is if you crush the thread you are cutting - and you would spot that in an instant. Could the problem lie elsewhere? Sometimes, very simple errors (yes, I know, I'm a bloke too) lead to huge frustrations. It could be as simple as forgetting to check that your verniers were zero'd before measuring.

 

[Penpal]

Pics now mate. It gets hypothetical real quick.

Peter.

 

[Bigblackdog]

before threading the section, what size did you turn the tenon down to?

 

[sfurini]

before threading the section, what size did you turn the tenon down to?

beat me to it....I was going to ask the same question. The tenon size should have been a hair under 10mm for your 10x.75 die...

 

[stiofanpadraigcrafts]

Pics now mate. It gets hypothetical real quick.

Peter.

i tried today as i worked all weekend, this time with the 12 x .75 and turned the tenon to the right size then cut the threads. zeroed the electronic caliper and measured the threads. they were 11.67mm in diameter.

 

[stiofanpadraigcrafts]

Stephen, it's unlikely to be down to the die to be honest. If you think it through, the crest of the male thread is what is left behind by the negative space of the die's major diameter, which is not is not a cutting surface. The trough of the male thread is what is cut by the die. The only way you can over egg the cake throgh over tightening a split die is if you crush the thread you are cutting - and you would spot that in an instant. Could the problem lie elsewhere? Sometimes, very simple errors (yes, I know, I'm a bloke too) lead to huge frustrations. It could be as simple as forgetting to check that your verniers were zero'd before measuring.

Hi Phil, i measured the threads after trying the 12 x .75 today and they end up at 11.67mm. i use digital calipers and zeroed them each time i turn them on. i'm sure its something simple and stupid i'm doing but at the minute its got me stumped

 

[stiofanpadraigcrafts]

the tap im using is this, its an intermediate tap.

 

[Penpal]

Thanks for the pics Stephen.

Peter.

 

[EStreet]

A M12x0.75 thread has a major of 12mm and a minor of 11.188mm. As for over tightening the die that is impossible as that is how you adjust the bite. On taps you have 3 (technically there are more) types of taps to use in progression but on dies there is just one, the adjustment is made via that screw.

Also you need to be using cutting fluid, try olive oil, pam or similarly thick viscosity and clean out the shavings very very often.

 

[stiofanpadraigcrafts]

A M12x0.75 thread has a major of 12mm and a minor of 11.188mm. As for over tightening the die that is impossible as that is how you adjust the bite. On taps you have 3 (technically there are more) types of taps to use in progression but on dies there is just one, the adjustment is made via that screw.

Also you need to be using cutting fluid, try olive oil, pam or similarly thick viscosity and clean out the shavings very very often.

im using wd40 as a cutting fluid

 

[EStreet]

WD40 may work for some materials but your cutting fluid does need to change based on the material. Try olive oil as well, I am not sure you mentioned the material but it appears to be some type of plastic, the purpose of the fluid is to coat the material so the threads cut cleaner. Cut slow and clean often, say maybe 1/4 of a turn. Run the die to the largest diameter you can and cut that, then tighten it to about half way and cut again. Repeat. Remember, soft and gentle will win your race for you. Aggressive and hard will net you disasters.

 

[stiofanpadraigcrafts]

WD40 may work for some materials but your cutting fluid does need to change based on the material. Try olive oil as well, I am not sure you mentioned the material but it appears to be some type of plastic, the purpose of the fluid is to coat the material so the threads cut cleaner. Cut slow and clean often, say maybe 1/4 of a turn. Run the die to the largest diameter you can and cut that, then tighten it to about half way and cut again. Repeat. Remember, soft and gentle will win your race for you. Aggressive and hard will net you disasters.

thanks for all he advice guys. i think i might have been destroying the threads when reversing the die back after finishing. i tried another and it seems to be a lot better. i started on ebonite but after a few mistakes i started to use delrin that i have for non stick bushings to practice on

 

[EStreet]

Ebonite has a compression factor to it that you must overcome when threading. It's workable and method makes all the difference in the world.

 

[EStreet]

Both of these are ebonite. The orange is very heavy dye and it cuts like crap and was extremely difficult to get good threads on it. The other image was not bad. The last photo is NYH ebonite and was very good to thread.

 

[stiofanpadraigcrafts]

i tried the ebonite again but every time i back out the threads are barely there. the delrin np but the ebonite im still having issues

Beautiful pens. they are great work